Use airline miles when the redemption gives you at least 1.3–1.5 cents per mile in value. Pay cash on discounted domestic economy fares, where miles redeem at less than 1¢ each.
Airline miles aren't "free trips." They're a currency with a fluctuating value. Here's the simple framework professional travel agents use to decide whether to redeem or pay cash.
The Cents-Per-Mile Benchmark
Calculate the value of your redemption: (Cash price – taxes/fees on award) ÷ Miles required. If the result is at or above the benchmark below, redeem. If below, pay cash and save the miles.
| Program | Good redemption value |
|---|---|
| Delta SkyMiles | ≥ 1.2¢ per mile |
| American AAdvantage | ≥ 1.4¢ per mile |
| United MileagePlus | ≥ 1.3¢ per mile |
| Southwest Rapid Rewards | ≥ 1.4¢ per point (fixed rate) |
| JetBlue TrueBlue | ≥ 1.3¢ per point |
| Alaska Mileage Plan | ≥ 1.5¢ per mile |
When Miles Almost Always Win
- International Business or First Class on a partner airline (often 3–8¢ per mile)
- Peak-season holiday flights when cash prices are extreme
- Last-minute bookings where cash prices have spiked
When Cash Almost Always Wins
- Discounted domestic economy fares (often under 1¢/mile redemption value)
- When you have low miles balance and unlimited cash
- When you need elite-qualifying segments / miles for status
Pro Tip: Transferable Points are King
Amex Membership Rewards, Chase Ultimate Rewards, Capital One miles, and Bilt Rewards transfer to multiple airline partners — letting you find the best sweet spot rather than being locked into one program's award chart.